{-# LANGUAGE CPP #-}
#if !defined(TESTING) && __GLASGOW_HASKELL__ >= 703
{-# LANGUAGE Trustworthy #-}
#endif
-----------------------------------------------------------------------------
-- |
-- Module      :  Data.IntMap.Lazy
-- Copyright   :  (c) Daan Leijen 2002
--                (c) Andriy Palamarchuk 2008
-- License     :  BSD-style
-- Maintainer  :  [email protected]
-- Stability   :  provisional
-- Portability :  portable
--
-- An efficient implementation of maps from integer keys to values
-- (dictionaries).
--
-- API of this module is strict in the keys, but lazy in the values.
-- If you need value-strict maps, use 'Data.IntMap.Strict' instead.
-- The 'IntMap' type itself is shared between the lazy and strict modules,
-- meaning that the same 'IntMap' value can be passed to functions in
-- both modules (although that is rarely needed).
--
-- These modules are intended to be imported qualified, to avoid name
-- clashes with Prelude functions, e.g.
--
-- >  import Data.IntMap.Lazy (IntMap)
-- >  import qualified Data.IntMap.Lazy as IntMap
--
-- The implementation is based on /big-endian patricia trees/.  This data
-- structure performs especially well on binary operations like 'union'
-- and 'intersection'.  However, my benchmarks show that it is also
-- (much) faster on insertions and deletions when compared to a generic
-- size-balanced map implementation (see "Data.Map").
--
--    * Chris Okasaki and Andy Gill,  \"/Fast Mergeable Integer Maps/\",
--      Workshop on ML, September 1998, pages 77-86,
--      <http://citeseer.ist.psu.edu/okasaki98fast.html>
--
--    * D.R. Morrison, \"/PATRICIA -- Practical Algorithm To Retrieve
--      Information Coded In Alphanumeric/\", Journal of the ACM, 15(4),
--      October 1968, pages 514-534.
--
-- Operation comments contain the operation time complexity in
-- the Big-O notation <http://en.wikipedia.org/wiki/Big_O_notation>.
-- Many operations have a worst-case complexity of /O(min(n,W))/.
-- This means that the operation can become linear in the number of
-- elements with a maximum of /W/ -- the number of bits in an 'Int'
-- (32 or 64).
-----------------------------------------------------------------------------

module Data.IntMap.Lazy (
            -- * Strictness properties
            -- $strictness

            -- * Map type
#if !defined(TESTING)
              IntMap, Key          -- instance Eq,Show
#else
              IntMap(..), Key          -- instance Eq,Show
#endif

            -- * Operators
            , (!), (\\)

            -- * Query
            , IM.null
            , size
            , member
            , notMember
            , IM.lookup
            , findWithDefault
            , lookupLT
            , lookupGT
            , lookupLE
            , lookupGE

            -- * Construction
            , empty
            , singleton

            -- ** Insertion
            , insert
            , insertWith
            , insertWithKey
            , insertLookupWithKey

            -- ** Delete\/Update
            , delete
            , adjust
            , adjustWithKey
            , update
            , updateWithKey
            , updateLookupWithKey
            , alter

            -- * Combine

            -- ** Union
            , union
            , unionWith
            , unionWithKey
            , unions
            , unionsWith

            -- ** Difference
            , difference
            , differenceWith
            , differenceWithKey

            -- ** Intersection
            , intersection
            , intersectionWith
            , intersectionWithKey

            -- ** Universal combining function
            , mergeWithKey

            -- * Traversal
            -- ** Map
            , IM.map
            , mapWithKey
            , traverseWithKey
            , mapAccum
            , mapAccumWithKey
            , mapAccumRWithKey
            , mapKeys
            , mapKeysWith
            , mapKeysMonotonic

            -- * Folds
            , IM.foldr
            , IM.foldl
            , foldrWithKey
            , foldlWithKey
            -- ** Strict folds
            , foldr'
            , foldl'
            , foldrWithKey'
            , foldlWithKey'

            -- * Conversion
            , elems
            , keys
            , assocs
            , keysSet
            , fromSet

            -- ** Lists
            , toList
            , fromList
            , fromListWith
            , fromListWithKey

            -- ** Ordered lists
            , toAscList
            , toDescList
            , fromAscList
            , fromAscListWith
            , fromAscListWithKey
            , fromDistinctAscList

            -- * Filter
            , IM.filter
            , filterWithKey
            , partition
            , partitionWithKey

            , mapMaybe
            , mapMaybeWithKey
            , mapEither
            , mapEitherWithKey

            , split
            , splitLookup

            -- * Submap
            , isSubmapOf, isSubmapOfBy
            , isProperSubmapOf, isProperSubmapOfBy

            -- * Min\/Max
            , findMin
            , findMax
            , deleteMin
            , deleteMax
            , deleteFindMin
            , deleteFindMax
            , updateMin
            , updateMax
            , updateMinWithKey
            , updateMaxWithKey
            , minView
            , maxView
            , minViewWithKey
            , maxViewWithKey

            -- * Debugging
            , showTree
            , showTreeWith
            ) where

import Data.IntMap.Base as IM

-- $strictness
--
-- This module satisfies the following strictness property:
--
-- * Key arguments are evaluated to WHNF
--
-- Here are some examples that illustrate the property:
--
-- > insertWith (\ new old -> old) undefined v m  ==  undefined
-- > insertWith (\ new old -> old) k undefined m  ==  OK
-- > delete undefined m  ==  undefined